Beliefs that coffee causes cancer or helps with weight loss have no scientific backing. Photograph: Graham Turner for the Guardian

Almost a 10th of adults mistakenly believe that coffee causes cancer, according to research by a leading charity.

The survey of 2,000 adults found 9% of those polled thought drinking it could lead to the disease while 10% saw caffeine as the key to weight loss.

But the World Cancer Research Fund said there was no scientific evidence for either assumption.

The WCRF said that research has in fact shown that coffee can have a preventative effect against womb cancer and there are suggestions it may protect against liver cancer.

Meanwhile, more than one in five believe caffeine is the "most dangerous" substance in coffee, when the highest health risk associated with the drink is sugar and full-fat milk or cream added to it, the charity said.

Dr Rachel Thompson, head of research analysis at the WCRF, said: "New evidence from our Continuous Update Project (CUP) suggests drinking coffee may decrease the risk of womb cancer, but there are still too many unanswered questions – such as how many cups we should drink, or how regularly – for us to provide any advice on coffee drinking.

"The CUP has found no consistent evidence that suggests coffee increases or decreases the risk of any other cancers but we are continually reviewing the evidence to see if this changes."

Sign up for the Guardian Today

Our editors' picks for the day's top news and commentary delivered to your inbox each morning.